1 - Used to describe a night that, due to excessive consumption of alcohol, is missing a substantial time period.
2 - Used to describe a drink that causes such a night.

The phrase Luke Gaffney derives from an actual person, one Mr Luke Gaffney, a rugby player from the North of England. When questioned about his drunken actions, Mr Gaffney frequently replied "I can't remember" in a thinly veiled attempt to preserve his dignity.

1. A) So what was your night like on Saturday?
B) I don't know, it was a bit of a Luke Gaffney.